The idea of "safety in numbers" clearly has its limits. Each year, crowd-related disasters kill hundreds of people, and have typically been hard to prevent. But now an intervention may be at hand, thanks to crowd simulations developed by Paul M. Torrens, a geographer at Arizona State University. Torrens's computer simulations let planners drop a few thousand virtual people into riot scenes and burning buildings, then sit back and take notes. The specific scenarios Torrens creates could show firefighters how to save the most people, tell architects where to place exits or barriers in stadiums, and guide police forces in corralling unruly mobs.
While most traditional crowd simulations treat individuals as purely physical, with no social or emotional reactions, Torrens's model turns each individual into an "avatar" with an artificial mind. Avatars can plan their own route, adjust their path on the fly, and even respond to the body language of fellow cybercitizens who may be jostling them.